SendFleet for WordPress

The official SendFleet plugin. Every email WordPress sends goes through the SendFleet API — your own Amazon SES (BYOC) or SendFleet's managed SES.

Paste an API key. That is the setup.

• Users: see readme.txt — it is the WordPress.org listing.
• API contract: docs.sendfleet.net (POST /v1/send, GET /v1/me).
• Brand: brand.sendfleet.net. Icons and banners in .wordpress-org/ are generated from the brand vectors by bin/generate-assets.mjs.

Contents

• How it works
• Repository layout
• Configuration
• Hooks for developers
• WP-CLI
• Development
• Testing
• Releasing

How it works

wp_mail()
  └─ pre_wp_mail filter ─────────────── Mailer            (skips when not connected or routing is off)
       └─ Message_Builder                (header parsing, wp_mail_* filters, phpmailer_init — exactly as core)
            └─ Envelope                  (verified sender, Reply-To, smoke-test rules, attachments, one entry per To/Cc/Bcc)
                 └─ Dispatcher           (one message per ≤50 recipients, one in To, one log row per recipient)
                      ├─ Transport ─── POST /v1/send   (circuit breakers, short inline retries)
                      ├─ Queue ─────── WP-Cron         (rate limits, 502/500 retries, background sending)
                      ├─ Fallback ──── PHPMailer       (optional)
                      └─ Log ───────── wp_sendfleet_log
Webhooks ── POST /wp-json/sendfleet/v1/webhook ── HMAC verified ── Log status + Suppressions
Account ─── GET /v1/me (cached) ── plan, usage, verified domains, smoke-test detection

Key decisions:

Repository layout

sendfleet.php                 Plugin header, constants, autoloader, hooks
uninstall.php                 Removes options, tables and cron events (multisite-aware)
readme.txt                    WordPress.org listing
includes/
  class-plugin.php            Wiring
  class-mailer.php            pre_wp_mail integration, source detection
  class-message-builder.php   Core-identical message assembly
  class-php-mailer.php        PHPMailer subclass (exposes queued IDN recipients)
  class-envelope.php          Sending rules → per-recipient request bodies
  class-dispatcher.php        Per-recipient outcome, log rows
  class-transport.php         One API call, breakers, inline retries
  class-queue.php             WP-Cron queue, maintenance
  class-fallback.php          PHPMailer fallback
  class-api-client.php        HTTP client (X-API-Key, no redirects)
  class-api-response.php      Response classification (error codes, retry classes)
  class-account.php           /v1/me snapshot, plans, domain routes, default sender
  class-attachments.php       Attachment allow-list and limits
  class-html-to-text.php      Plain-text alternative
  class-mime-parser.php       Hand-built multipart bodies
  class-log.php               Log + queue table
  class-suppressions.php      Local suppression list
  class-webhooks.php          REST receiver
  class-settings.php          Options + wp-config constants
  class-crypto.php            Secret encryption
  class-state.php             Breakers and diagnostics
  class-status.php            Health issues (notices, Site Health)
  class-site-health.php       Site Health test + debug info
  class-privacy.php           Exporter, eraser, policy text
  class-test-email.php        Test email
  class-cli.php               WP-CLI commands
  admin/                      Menu, screens, list table
  views/                      Screen templates
assets/                       Admin CSS/JS, the mark
languages/sendfleet.pot       Translation template
tests/mock-api/server.js      Mock SendFleet API (no dependencies)
tests/e2e/                    Scenario suite, runner, test mu-plugin
bin/build.sh                  Builds dist/sendfleet-<version>.zip
bin/generate-assets.mjs       Builds .wordpress-org/ icons and banners
.wordpress-org/               Directory assets (icons, banners, screenshots)

Configuration

Everything is in SendFleet → Settings. Constants in wp-config.php override the stored values:

Hooks for developers

Core's wp_mail_succeeded and wp_mail_failed fire as usual; failures carry the per-recipient results under sendfleet in the error data.

WP-CLI

wp sendfleet status [--refresh] [--format=json]
wp sendfleet connect <key>
wp sendfleet test [<to>] [--from=<address>]
wp sendfleet queue [list|run]
wp sendfleet refresh
wp sendfleet purge-log [--older-than=<days>] [--yes]

Development

Requirements: PHP 7.4+, Composer, Docker (for the test environment), Node (mock API, asset generation).

composer install          # PHPCS + WordPress Coding Standards + PHPCompatibilityWP
composer lint             # vendor/bin/phpcs
composer lint:fix         # vendor/bin/phpcbf

docker compose up -d      # WordPress on :8088, Mailpit on :8025, mock API inside the network
bash tests/e2e/run.sh     # install, activate, run every scenario
bash tests/e2e/run.sh down  # tear down containers and volumes

Log in at http://localhost:8088/wp-admin (admin / admin). Test keys accepted by the mock (<prefix>. followed by 32 × a):

Special recipients on the mock: fail502@…, flaky502@…, fail500@…, throttle@…, slow@….

Testing

Releasing

1. Bump the version in three places: the Version: header and SENDFLEET_VERSION in sendfleet.php, and Stable tag: in readme.txt. Add a changelog entry. (bin/build.sh refuses to build if they differ.)
2. Regenerate the translation template if strings changed: wp i18n make-pot . languages/sendfleet.pot --slug=sendfleet --exclude=vendor,tests,build,dist,bin,node_modules
3. Commit, then tag with the bare version and push: git tag 1.0.1 && git push origin main 1.0.1.
4. .github/workflows/release.yml runs CI's lint and end-to-end checks and, only if they pass, builds the zip, deploys it to WordPress.org SVN (trunk + tag + assets) and attaches it to a GitHub release. It needs the SVN_USERNAME and SVN_PASSWORD repository secrets.

License: GPL-2.0-or-later.